Sphinx Project 9 cd motor not running after laser change

[muizel]

Hello people,
I bought a sphinx project 9 cdplayer but it couldn't read cd's, so i changed the laser from the CDM1 MK2 and tried if it was ok, (the laser is from an old player that was working) . But now the cd disk is not rotating, everything works display, drawer in and out i can see the laser arm moving and focussing but the motor is not spinning the disk, the i put back the old defect laser and stil no spinning disk, i also took a look at the hall motor changed the 4 transistors and 1 ic, measured the coils of the motor but still no running, i also noticed that when the power is on the and you turn the cd by hand the motor is breaking a little when the power is of than the cd turned by hand runs freely.

Anyone an idea i am very keen in fixing this nice player.

Thanks in advance and sorry for the bad english.

Rene.

[stephensank]

On cdm-1 era players, the first thing always to do is resolder very thoroughly the points where the top ground plane is soldered through to connections on the bottom side of the big main servo PCB.
Secondly, about the only other thing that goes wrong on these units is thrust bearing wear on the platter motor. So, if you have done the servo board soldering, try turning the thrust bearing clockwise(looking from under the player, with a T10 or perhaps T15 torx driver) 1/4 of a turn at a time until the laser is able to focus & starts up the disc.

[muizel]

Originally posted by stephensank
On cdm-1 era players, the first thing always to do is resolder very thoroughly the points where the top ground plane is soldered through to connections on the bottom side of the big main servo PCB.
Secondly, about the only other thing that goes wrong on these units is thrust bearing wear on the platter motor. So, if you have done the servo board soldering, try turning the thrust bearing clockwise(looking from under the player, with a T10 or perhaps T15 torx driver) 1/4 of a turn at a time until the laser is able to focus & starts up the disc.

Thanks Stephen,

All the points you mentioned are allright, I am getting desperate because it is a rare beauty this player.

Regards Rene.

[muizel]

Somebody can help please pelease

[stephensank]

Without the unit in front of my eyes, the only other thing I can think of, off hand, is to check all of the fusible resistors. These are usually 10ohm or lower & with silver/grey bodies, and can fry open without showing it. So, measure all that you can find with an ohmmeter & see if any are way over value/open. If one is fried, check on both ends of it for a short or near short to ground, as it more likely than not, fried due to a shorted electrolytic cap it is feeding voltage to. Speaking of lytics, if it were my player, I would just go ahead & replace every lytic that is not already a Nichicon with a Nichicon or NipponChemicon, just for the sake of long term reliability. The lytics that fail in these old Philips players are invariably Philips, Siemens or other German made lytic, just as in any Studer/Revox gear.

[muizel]

Originally posted by stephensank
Without the unit in front of my eyes, the only other thing I can think of, off hand, is to check all of the fusible resistors. These are usually 10ohm or lower & with silver/grey bodies, and can fry open without showing it. So, measure all that you can find with an ohmmeter & see if any are way over value/open. If one is fried, check on both ends of it for a short or near short to ground, as it more likely than not, fried due to a shorted electrolytic cap it is feeding voltage to. Speaking of lytics, if it were my player, I would just go ahead & replace every lytic that is not already a Nichicon with a Nichicon or NipponChemicon, just for the sake of long term reliability. The lytics that fail in these old Philips players are invariably Philips, Siemens or other German made lytic, just as in any Studer/Revox gear.

Thanks Stephen,

I already checked the resistors and caps they are allright, today I spend again several hours with the player and put in another good working laser assembly, but still it is not working.

What happens is when I turn the power on the laser arm of the cdm1 mk2 nocks with a loud klick to the outside off the drive and stay's there, you can see the lens focus, that's all and the disk motor (it's a hall type) is not running the disk, and when i turn the disk a little by hand the motor seems to break a little, i mean the disk is not running free, when i turn the power off the breaking is over and the disk runs well when you give it a turn by hand.

The only parts i didnt replaced are the TDA8809 and TDA8808 could they give me this problems ??

Regards Rene.

[kevinkr]

The 8808 and 8809 are discontinued but a couple of vendors in the UK still had them a couple of years ago. Likely though that it is something more directly related to the motor drive electronics which is a different chip. Check the wiring to the motor..

[muizel]

Originally posted by kevinkr
The 8808 and 8809 are discontinued but a couple of vendors in the UK still had them a couple of years ago. Likely though that it is something more directly related to the motor drive electronics which is a different chip. Check the wiring to the motor..

Thanks Kevin,

For this hall motor to run it needs a sinus signal on it's input and that seems to be the problem, I already checked the total motor circuit and that seems fine also the power supply to the motor is ok, but I can't get to figure out why there is no sinus signal . The problem is that there is no way to get a service manual these Sphinx Project nine players are very rare, and there is almost nothing to find about it. Somehow there must be a way to get it fixed it is such a nice cdplayer.


Regards René.

[kevinkr]

Hi Rene,
Using the cited chips I suspect it could be quite similar to the Philips reference application. There were a couple of rotel players that used the standard Philips chip family and the servo and motor driver design were virtually identical to what was used in my old Lambda Drive. I will try to see if I can get that rotel model # and post it here.

[guido]

CD80 and Philips CD880 use it. Get a manual for one of those and you will probably find the fault. As for those ic's, plenty of them at your local "kringloopwinkel".

Guido